Blowtorch



April 14, 1931. p, FQRSTER 1,800,616

BLOWTORCH Filed Dec. 10. 1929 INVE T R. 7 12A; 7%.

A TTORNEYS.

Patented A r. 14, 1931 PATENT OFFICE PERCY I. FOBSTEB, OI BERKELEY, CALIFORNIA Application filed December 10, 1929. Serial No. 418,064.

hThis indvenpiondrelates to blocyv torcheis of t at e iscose inm co n in appication eiititled Torch, filed Nove mber '26, 1929, Ser. No. 409,837, and has for its principal object the provision of a simple and eflicient blow torch utilizing'natural gas as a fuel.

In carrying the invention into practice the air and natural gas are first admitted to a mixing chamber in which baflles are arranged so that the gas and air will be thoroughly mixed before being ejected at the burner tip. The burner tip is so constructed that streams of the gaseous mixture are caused to conver e at a point just be 0nd the burner tip so t at sharp intense ame will be created. In order to obtain a flame of greater heat than that provided by just natural gas and air I have provided means fordelivering additional oxygen and compressed air to the burner tip.

One form which the invention may assume is exemplified in the following description and illustrated by way of exam 1e in the accompanying drawings, in whic Fi 1 is a side elevation of a torch embodying the preferred form of my invention.

Fig. 2 is a central section through the 8 same. I

Referring more particularly to the accompanying drawings, 10 indicates a torch or burner utilizing natural gas as a fuel. This torch or burner comprises a casing 11 which encloses a mixing chamber 12. The ends of the casing 11 are closed. Connected with one end of the casing is an inlet pipe 14 fitted with a T 15 to which is connected a compressed air pipe 16 and a pipe 17 for delivering natural gas to the pipe'14. The pipes 16 and 17 are each fitted with a valve so that the quantity of compressed air and natural gas delivered to the pipe 14 may be regulated. At the opposite end of the cars ing 11 is a delivery. pipe 18, the outer end of which terminates in a burner tip 19.

The interior of-the casing 11 is so baflled that the natural gas and air admitted thereto through the pipe 14 will be thoroughly mixed before it is delivered to the pipe 18 and discharged at the burner tip 19.

Reference being had to the drawings it will be noticed that just within the end of the casing 11 into which the pipe 14 pro- 5 jects is a curved bafiie plate 20, one end of which is not in contact with the casing 11 so that the air and gas entering the chamber will be caused to swirl and pass around the free end of the baffle 20. m

At spaced intervals beyond the baflle 20 are perforated plates 21, two of which are provided with a series of perforations while the other is provided with a sin leperforation'. These perforated plates a so assist in 5 causing the gas and air to thoroughly mix. As the gas and air pass through the last baifie plate 21 they engage a cupped bafile plate 22 secured on the inner end of the pipe 18. This enga ement causes the gas and air to swirl as t ey must pass around the plate 22 before entering the orts 23 in the pipe 18. The series of ba e plates just mentioned causes the gas and air to thoroughly mix .while passing through the chamber 12.

It is desired to point out that the lack of oxygen in natural gas prevents it from igniting until it has mixed with a suflicient quantity of oxygen. .Thus, if the natural 30 gas and air were ejected separately directly at the nozzle the flame would be spaced from the nozzle and result in an inoperative burner. I overcome this, of course, by first thoroughly mixin the air and gas 86 before discharging it un er pressure from v the nozzle.

Surrounding the burner tip 19 is a cylindrical shield 24.- which is of a diameter somewhat larger than the burner ti 19. The space between the inner end 0 the shield 24 and the pipe 18 is closed as at 25 while the outer end of the shield is 0 en.

Arranged exteriorly about t e shield 24 is a series of small tubes 26 which are con- 05 nected at their inner ends 27 with the pipe 18 while their outer ends are connected with the shield 24 just beyond the tip 19. The ended the feed tubes 26 which communicats with the outer end of the .shield 24.- 39

axis of the shield 24 so that the small fine streams of gas dischar ed from the tubes 26 ing additional air under pressure or oxygen to the burner-tip. This means comprises a pairof fine tubes-3O andBl which extend" will convergetoward t e center of the shield and thus make a very fine sharp flame when the torch is in operation. 7

In order to .create a hotter flame when: e

I gas and air is delivered, said; casing being fitted interiorly with bafiie plates for desired I have-provided means for deli-veralong "the casing 11' and thence centrally through the pipe 18 to a ppintat the burner tip 19. These tubes are oth controlled by valves 32. One of the tubes is connected to a. source of oxygen while'th'e other is a connected with a source of compressedair.

It will be'noted thatfas' the oxygen de-' livery tube extends 'to the tip'it does not;-

mix with the gas at any time'until the gas leaves the tip, thus preventing any danger of explosion.

not be blown out when air :lor oxygen is delivered from the pipes and 31; In operationfof the device compressed air 7 delivery to the pipe 18. ,As, 'the gaseous mixture thus formed discharges from. the

, up 19 itis ignited. The suction created will draw the gaseous mixture through the tubes 26,andcause a plurality of fine flames to converge toward the vcenter of the tip V v through'the I also desire to point .outthat the streams? of gas andyair ejected} from the small tubes i 26 are directed to a pointv vhere they will ameter than the tip arranged concentrically-f thereabout, a pluralit of. small tubes con nected with the shiel 'for directing a plurality of converging'flames toward the con tenof the shield at apointjustbeyond the 3. A torch comprising .a casing tolwhich mixing "the gas and air, a pipe extending from. the; casing and terminating in a with said pipe and the other end with said shield, saidstubes at the point where they join the shield being; angularly disposed whereby a plurality ofvstreamsiof gas'and air will be caused tojconverge toward the; center of the shield at'a point just beyond the tip, and separate oxygen and compressed air delivery tubes extending T i centrally pipe and terminating at the tip.

' PERCY EORSTER.

creating a sharp and intense flame which, 7 p p of. course, is very; desirable.

To make the flame hotter so that it may be used for burning and welding,'additional 1 compressed air or oxygen-may. bedelivered to the burner'tiplthrough the pipes 30 and 31; I have found in actual ractice that' a burnerconstructed in accor ance with the invention justfdisclosed is .very eflicient for use in connection with natural as.

departing from the, spirit of the invention ral tip,r a cylindrical shield of a larger di-- While I have shownthe pre erred form I I I 'Iof'my invention, it is to'be understood that varlous changes'may be made inits conf'struction by those skilled in the art without asdefined in theappended claims. I

I" claim and desire to secure by 7 Letters Patent iis: .7 I e '1. A burner nozzle comprising a cylindrical burnertip, a cylindrical shield arranged concentrically thereabout, and a plurality of separate fuel ducts surrounding the shield for directing flames converging toward the 3 center of the tip at 'a point just beyond the same. 7 V

2 A burner nozzle comprising-a cylindri- 7 Having thus described my invention, what i 

